Data Communication System and Method for Preventing Packet Proliferation in a Multi-Device Link Aggregation Network

1. A first edge device for relaying a packet over a VPLS (Virtual Private LAN (Local Area Network) Service) in a first network located between a second network and a third network, the first edge device comprising: a controller; and a network interface, wherein the first edge device and a second edge device provide multi-chassis link aggregation to the second network, wherein the first edge device sends, to a third edge device over the VPLS in the first network, a control instruction for MAC (Media Access Control) learning of packets that are relayed by the third edge device, and wherein the third edge device receives an instruction to delete information which has been learned when either the first edge device or the second edge device is detected as failed.

2. The first edge device according to claim 1 , wherein the first edge device sends a control message to the second edge device which is one of other devices of the multi-chassis link aggregation, wherein the first edge device determines a condition of the second edge device according to a status of exchanging the control message, and wherein the first edge device sends, to the third edge device, the control instruction to delete MAC learning information which has been learned by the third edge device if the second edge device is determined to be failed.

3. The first edge device according to claim 1 , wherein the first edge device is configured to send, to the third edge device, the control instruction to delete MAC learning information which has been learned by the third edge device if the second edge device is determined to be failed.

4. The first edge device according to claim 1 , wherein information obtained by the MAC learning includes at least one of a MAC address stored in at least one of a destination and a sender of a packet, and an identifier of a virtual circuit as an interface of the VPLS from a redundant system via the VPLS.

5. The first edge device according to claim 1 , wherein the first edge device is preset to transfer a packet from the second network towards to the third edge device via the VPLS, and the second edge device is preset to transfer a packet from the second network when the first edge device is detected to be failed.

6. The first edge device according to claim 1 , wherein the first edge device transfers a packet from the second network towards to the third edge device via the VPLS instead of the second edge device which has failed.

7. The first edge device according to claim 1 , wherein the first edge device is located on a same edge side with the second edge device which provides multi-chassis link aggregation, and is located on a different edge side to the third edge device in the VPLS.

8. A communicating method for relaying a packet via a VPLS (Virtual Private LAN (Local Area Network) Service) in a first network between an edge system of a first edge device and a second edge device, and a third edge device, the method comprising the steps of: providing, by the edge system, a multi-chassis link aggregation to a communication device in a second network; relaying, by the edge system, a packet received from the second network, to the third edge device via the VPLS; learning, by the third edge device, information of a packet from the edge system via the VPLS; and sending, to the third edge device, an instruction that deletes information which has been learned when detecting, by the edge system, that either the first edge device or the second edge device is failed.

9. The communicating method according to claim 8 , wherein the step of the relaying the packet received from the second network, to the third edge device via the VPLS is performed by a preset device between either the first edge device or the second edge device in the edge system after the VPLS is established, and is performed by another edge device than the preset device in the edge system when the preset device is failed.

10. The communicating method according to claim 9 , wherein the step of the learning begins in response to an instruction from the edge system.

11. The communicating method according to claim 9 , wherein the learned information includes at least one of a MAC (Media Access Control) address stored in a destination and a sender of a packet from the edge system via the VPLS, and an identifier of a virtual circuit as an interface of the VPLS from the edge system via the VPLS after deleting a MAC address which has been learned.

12. The communicating method according to claim 8 , further comprising the steps of: exchanging a control message between the first edge device and the second edge device; and determining, by the edge system, the first edge device or the second edge device is failed according to a status of exchange of the control message.

13. A communicating system for relaying a packet over a VPLS (Virtual Private LAN (Local Area Network) Service) in a first network between a second network and a third network, comprising: a first edge device coupled to the second network; a second edge device coupled to the second network; and a third edge device coupled to the third network, wherein the first edge device and the second edge device provide the second network with multi-chassis link aggregation, wherein the first edge device sends, to the third edge device, control instructions for MAC (Media Access Control) learning of packets that are relayed by the third edge device, wherein at least one of the first edge device and the second edge device relays a packet received from the second network to a third device via the VPLS established in the first network, wherein the third edge device learns information of a packet received from at least one of the first edge device and the second edge device via the VPLS, and wherein at least one of the first edge device and the second edge device sends, to the third edge device, an instruction that deletes information which has been learned when either the first edge device or the second edge device is failed.

14. The communicating system according to claim 13 , wherein the first edge device and the second edge device exchange a control message with each other and determine that the first device or the second device is failed according to a status of receipt of the control message.

15. The communicating system according to claim 13 , wherein when a packet from the second network is relayed to the third device via the VPLS by a preset edge device between either the first edge device or the second edge device after the VPLS is established, and a packet from the second network is relayed to the third device by another an othcr device than a preset edge device in the first edge device or the second edge device when the preset edge device is failed.

16. The communicating system according to claim 15 , wherein the third edge device starts the MAC learning after at least one of the first edge device and the second edge device sends, to the third edge device, an instruction related to the MAC learning.

17. The communicating system according to claim 15 , wherein information obtained by the MAC learning includes at least one of a MAC address stored in at least one of a destination and a sender of a packet, and an identifier of a virtual circuit as an interface of the VPLS from either the first edge device or the second edge device via the VPLS.

18. A communication system for relaying a packet comprising: a first edge device coupled to a first network and a second network; a second edge device coupled to the first network and the second network; and a third edge device coupled to the second network and a third network, wherein the first edge device and the second edge device provide the second network with a redundant configuration for the first edge device and the second edge device, wherein at least one of the first edge device and the second edge device relays a packet received from the second network to the third device via the first network, wherein the third edge device learns MAC (Media Access Control) address information of a packet received from at least one of the first edge device and the second edge device via the first network, and wherein at least one of the first edge device and the second edge device sends, to the third edge device, an instruction that deletes MAC address information which has been learned when either the first edge device or the second edge device is failed.

19. A first edge device for relaying a packet in a first network located between a second network and a third network, the first edge device comprising: a controller; and a network interface, wherein the first edge device provides the second network with a redundant configuration for the first edge device and a second edge device, wherein the first edge device sends, to a third edge device over a VPLS (Virtual Private LAN (Local Area Network) Service) in the first network, a control instruction to delete MAC (Media Access Control) learning information which has been learned by the third edge device if the second edge device is determined to be failed, and wherein the third edge device receives an instruction to delete information which has been learned when either the first edge device or the second edge device is detected as failed.

20. The first edge device according to claim 19 , wherein the first edge device sends a control message to the second edge device, and wherein the first edge device determines a condition of the second edge device according to a status included in the control message.